CVE-2021-39933
An issue has been discovered in GitLab CE/EE affecting all versions starting from 12.10 before 14.3.6, all versions starting from 14.4 before 14.4.4, all versions starting from 14.5 before 14.5.2. A regular expression used for handling user input (notes, comments, etc) was susceptible to catastrophic backtracking that could cause a DOS attack.
Source: CVE-2021-39933